Developing and fixing exposed silver succindiamidoxime



DEVELOPING AND FIXING EXPOSED SILVER SUQCINDIAMKDOXIME Marilyn Levy, Red Bank, N. 1., and Nash A. Kidd, Freeport, Tex., assignors to the United States of America as represented by the Secretary of the Army No Drawing. Application August 13, 1956 Serial No. 603,849

7 Claims. (Cl. 96--61) (Granted under Title 35, U. S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon.

This invention relates to new photographic elements and is based on the discovery that a colloidal dispersion of silver succindiamidoxime in certain colloid carriers after exposure to light will form a latent image which is subsequently developable by exposure to steam. The exposed and developed light sensitive layer can then be fixed to further decomposition by light with ammonia. The light sensitivity of these new photographic elements may be increased by sensitizers.

The details of the invention will become more apparent from the following description of specific embodiments of the broad inventive idea.

Example 1 Ten grams of a film forming vinyl polymer solution such as a 12 to 15% solution of polyvinyl butyral in a volatile solvent (ethyl alcohol, isopropyl alcohol or the like) are mixed with .3 cc. of glycerin, 1 gm. of silver succindiamidoxime and 1 to 2 cc. of sodium lauryl sulfate as a sensitizer (2% in water), until the silver salt is dissolved in the colloidal solution. The solution is then cast down on paper, glass or any other supporting medium and dried for 24 hours in a dark-room. A faint print-out image is obtained after exposure for five seconds at a distance of 1 foot from a Hanovia U. V. source. The image darkens considerably when held over a steam bath for about 30 seconds. Dry heat, however, will not develop the image. The photo-sensitive layer is then fixed by immersion in a 1 normal solution of ammonia. The developing and fixing operation can be done in one-step by the use of hot ammonia, that is, by treating the exposed photographic element with steam containing ammonia vapors.

Instead of using 1 to 2 cc. of the sodium lauryl sulfate solution mentioned above, 2 to 4 cc. of a quarternary ammonium salt solution (2% in alcohol) may be used. Dodecyldimethylammoniumchloride or octodecyldimethylammoniumchloride have proved to be particularly efiective as sensitizcrs showing greater increase in density on steam development than formulations containing sodium lauryl sulfate.

Example 2 One gram silver succindiamidoxime is dispersed in lee cc. of a 5% gelatin solution. The mixture of the silver salt and the gelatin is then agitated at 40 C. and 8 cc. of a 2% solution of sodium lauryl sulfate are added. The mixture is then passed through a stainless steel homogenizer and coated on a paper or glass support.

Example 3 1.5 gm. of silver succindiamidoxime were dispersed in 5 ml. of a 3% gelatin solution at 40 C. with agitation. An additional 15 cc. of the gelatin solution is added after about one minute agitation and the mixture is then treated as described in Example 2.

After exposure for one-fifth second to a Hanovia U. V. source located 6 inches away from the slide a visible image develops in the formulations given above by means of steam. The photosensitive layer is then fixed by immersion in an aqueous solution of ammonium. Various concentrations between 2 to 20% of concentrated ammonia in water may be used.

The new photographic elements made according to this invention may be used in a one-step photographic or reproduction system. Instead of sodium lauryl sulfate many other sensitizers may be added preferably in a 2% solution in an organic solvent such as sodium 2-ethyl hexene sulfonate, sodium tetra decyl sulfate, sodium dioctyl phosphate, sodium heptadecyl sulfate, polyethylene glycol alkyl others and sodium 2-ethyl hexene sulfonate.

It will be understood by those skilled in the art that many variations and combinations are feasible within the broad inventive idea as defined in. the following claims.

What is claimed is:

1. The method of forming a visible image in an organic colloid carrier having dispersed therein silver succindiamidoxime comprising developing the exposed carrier by treating it with steam and then fixing it with ammonia.

2. The method of forming a visible image according to claim 1 comprising developing and fixing the exposed carrier by treating it with steam containing ammonia vapors.

3. The method of forming a visible image according to claim 1 in which the organic colloid carrier contains sodium lauryl sulfate as a sensitizer.

4. The method of forming a visible image according to claim 1 in which the organic colloid carrier contains sodium 2-ethyl hexene sulfonate as a sensitizer.

5. The method of forming a visible image according to claim 1 in which the organic colloid carrier contains sodium tetra decyl sulfate as a sensitizer.

6. The method of forming a visible image according to claim 1 in which the organic colloid carrier contains sodium dioctyl phosphate as a sensitizer.

7. The method of forming a visible image according to claim 1 in which the organic colloid carrier contains sodium heptadecyl sulfate as a sensitizer'.

References Cited in the file of this patent UNITED STATES PATENTS 2,759,819 Levy, et a1. Aug. 21, 1956 

1. THE METHOD OF FORMING A VISIBLE IMAGE IN AN ORGANIC COLLODIAL CARRIER HAVIGN DISPERSED THERIN SILVER SUCCINDIAMIDOXIME COMPRISING DEVELOPING THE EXPOSED CARRIER BY TREATING IT WITH STEAM AND THEN FIXING IT WITH AMMONIA. 